Today there are various platforms having tracks, said platforms being available for various applications. A drilling rig may be an example of such a platform having tracks. Said drilling rig may for an example be arranged for operation on a ground surface. Hereby the drilling rig may be arranged for performing various kinds of construction works.
Said platforms may be controlled by an operator, i.e. a driver may control propulsion and operation of for example tools or machines of the platform from a cabin. Alternatively said platforms may be radio controlled/remote controlled.
Said platform may be arranged for being controlled by means of so called track control. These platforms may be propelled by means of tracks or wheels. Hereby a speed of a track on a first side and speed of a second track on a second side may be controlled manually by means of suitable electronic or mechanical actuator means, for example a steering wheel and an accelerator pedal. The platform may thus be made to turn by applying different speeds of said first track and said second track.
At propulsion of the platform involving making turns various disadvantages may occur. In particular these disadvantages may occur when changing propulsion direction when propulsion is performed on a wet, muddy or sandy surface where relatively large forces are applied by means of the tracks for turning the platform about a rotational axel of the same.
These disadvantages may partly relate to tricky operation of the platform where an operator has to perform gear shifts of a transmission of a platform at same time as he must keep watch for safe propulsion. Further, the driver in some cases also has to consider carried equipment, such as for example drilling devices, during propulsion of said platform. Propulsion of a platform with two tracks may be perceived as complex by an operator, in particular when turning, because a number of work tasks needs to be carried out simultaneously or substantially simultaneously.
These disadvantages may relate to non-desired changes of operation conditions of the platform. These changes of operational conditions may relate to non-desired reduction of a current engine speed of an engine of the platform due to increased load of the platform arising during said changes of propulsion direction. Hereby non-desired stalling of the engine may occur. In certain situations said tracks hereby stop if an increased load of the platform becomes too large.
U.S. Pat. No. 7,290,390 B2 depicts a control device for a hydraulic excavator of crawler type where a slow start is provided during manual operation thereof.